Original address

[dmoranj]

Add a property in the response listener for the requests to allow the caller to retrieve information about the socket used in the communication (port, address and protocol). This addition was motivated by the need of identifying the device original address in COAP-based OMA Lightweight M2M protocol as explained in issue #39 (originally the need was to use the same socket for listening and sending requests, but having information about the registration socket might lead to avoid the sharing, as explained in a comment).

I choose to expose the information as part of the rsinfo object (that was already passed to the IncomingMessage instance creation) and expose the latter in a _rsinfo internal attribute of the response, but I'm not 100% confident this is the best option. It covers the functionality specified in the issue, though.

[mcollina]

I'm ok with adding that visibility of the local address, however, I am not sure that _rsinfo is the right place for it. I would likely expose the rsinfo as rsinfo as it would become part of the external interface, and document that in the README. But I would also keep that untouched (as from the UDP socket itself) and add one more property.

Also, you would need to add them to https://github.com/mcollina/node-coap/blob/master/lib/observe_read_stream.js.

[dmoranj]

Ok. I'll expose the rsinfo as is and the outgoing socket as an outSocket one, and add the docs for both.

[dmoranj]

Information about both sockets exposed as external attributes and added to their respective sections in the documentation.

[mcollina]

@dmoranj are you ok to become a collaborator of this project? Have a look at https://github.com/mcollina/node-coap/blob/master/CONTRIBUTING.md and let me know!

[dmoranj]

Sorry, didn't read this message until now. Yes, I would like to become a collaborator (I guess I'll be working extensively with COAP in the next months, so I hope I'll have time to contribute).